The present invention relates to a multi-layer substrate, including laminated conductor layers and insulation layers, for carrying an integrated semiconductor chip.
Generally, the multi-layer wirings are achieved through the use of plural printed circuit boards, a thick film method and printing techniques. There are several methods utilizing the printing techniques.
1. Conductor layers and insulator layers are laminated by alternatingly printing them and firing them. PA1 2. Conductor patterns are printed on a green ceramic substrate. Plural of the thus formed green ceramic substances are stacked and attached to each other to form a laminated ceramic substrate. PA1 3. Conductor layers and insulator layers are alternatingly printed on a green ceramic substrate, and they are sintered at the final step. This method is termed as a green sheet printing method.
The above-mentioned conventional multi-layer substrate is not suited for a high power chip, since the base plate is made of either ceramics or glass. Moreover, the conventional multi-layer substrate does not show satisfying high-insulation characteristics.